The aim of the paper is to reevaluate the theoretical dimension of the book “History of Byzantine Art and Iconography Based on Miniatures of Greek Manuscripts” (1876) by the leading Russian art historian Nikodim Pavlovich Kondakov (1844-1925) within the context of examining the cultural and social problem of decadence. The article provides a new interpretation of the well-known work by N. P. Kondakov. Scientific novelty lies in the following: the terminology of the book (and, above all, such concepts as naturalism, realism and idealism) is considered for the first time in connection with the problems of biological and decadent discourses. Particular attention is paid to the social and cultural aspects of the cyclical theory of decline set forth in Nikodim Kondakov’s book. As a result, this concept of cultural degradation is linked with ideas about social decline that were formed in the culture of the 19th century. The components of the aesthetics of decadence and biological discourse are studied, among other things, through the lens of Russian realistic aesthetics. The article uses methodological complexes that help shed new light on the peculiarities of the functioning of the cultural tradition in the Russian Empire in the second half of the 19th century, especially in aspects related to the influence of culture on the development of the humanities. The emphasis is on finding those cultural and intellectual sources of Nikodim Kondakov’s scientific activity that turned out to be the most important in terms of the formation of his innovative theoretical and methodological concepts.